if (L.Proj) {
  L.CRS.Baidu = new L.Proj.CRS(
    "EPSG:900913",
    "+proj=merc +a=6378206 +b=6356584.314245179 +lat_ts=0.0 +lon_0=0.0 +x_0=0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext  +no_defs",
    {
      resolutions: (function () {
        var level = 19;
        var res = [];
        res[0] = Math.pow(2, 18);
        for (var i = 1; i < level; i++) {
          res[i] = Math.pow(2, 18 - i);
        }
        return res;
      })(),
      origin: [0, 0],
      bounds: L.bounds([20037508.342789244, 0], [0, 20037508.342789244]),
    }
  );
}

L.TileLayer.ChinaProvider = L.TileLayer.extend({
  initialize: function (type, options) {
    // (type, Object)
    var providers = L.TileLayer.ChinaProvider.providers;

    options = options || {};

    var parts = type.split(".");

    var providerName = parts[0];
    var mapName = parts[1];
    var mapType = parts[2];

    var url = providers[providerName][mapName][mapType];
    options.subdomains = providers[providerName].Subdomains;
    options.key = options.key || providers[providerName].key;

    if ("tms" in providers[providerName]) {
      options.tms = providers[providerName]["tms"];
    }

    L.TileLayer.prototype.initialize.call(this, url, options);
  },
});

L.TileLayer.ChinaProvider.providers = {
  TianDiTu: {
    Normal: {
      Map: "//t{s}.tianditu.gov.cn/DataServer?T=vec_w&X={x}&Y={y}&L={z}&tk={key}",
      Annotion:
        "//t{s}.tianditu.gov.cn/DataServer?T=cva_w&X={x}&Y={y}&L={z}&tk={key}",
    },
    Satellite: {
      Map: "//t{s}.tianditu.gov.cn/DataServer?T=img_w&X={x}&Y={y}&L={z}&tk={key}",
      Annotion:
        "//t{s}.tianditu.gov.cn/DataServer?T=cia_w&X={x}&Y={y}&L={z}&tk={key}",
    },
    Terrain: {
      Map: "//t{s}.tianditu.gov.cn/DataServer?T=ter_w&X={x}&Y={y}&L={z}&tk={key}",
      Annotion:
        "//t{s}.tianditu.gov.cn/DataServer?T=cta_w&X={x}&Y={y}&L={z}&tk={key}",
    },
    Subdomains: ["0", "1", "2", "3", "4", "5", "6", "7"],
    key: "174705aebfe31b79b3587279e211cb9a",
  },

  GaoDe: {
    Normal: {
      Map: "//webrd0{s}.is.autonavi.com/appmaptile?lang=zh_cn&size=1&scale=1&style=8&x={x}&y={y}&z={z}",
    },
    Satellite: {
      Map: "//webst0{s}.is.autonavi.com/appmaptile?style=6&x={x}&y={y}&z={z}",
      Annotion:
        "//webst0{s}.is.autonavi.com/appmaptile?style=8&x={x}&y={y}&z={z}",
    },
    Subdomains: ["1", "2", "3", "4"],
  },

  Google: {
    Normal: {
      Map: "//www.google.cn/maps/vt?lyrs=m@189&gl=cn&x={x}&y={y}&z={z}",
    },
    Satellite: {
      Map: "//www.google.cn/maps/vt?lyrs=s@189&gl=cn&x={x}&y={y}&z={z}",
      Annotion: "//www.google.cn/maps/vt?lyrs=y@189&gl=cn&x={x}&y={y}&z={z}",
    },
    Subdomains: [],
  },

  Geoq: {
    Normal: {
      Map: "//map.geoq.cn/ArcGIS/rest/services/ChinaOnlineCommunity/MapServer/tile/{z}/{y}/{x}",
      PurplishBlue:
        "//map.geoq.cn/ArcGIS/rest/services/ChinaOnlineStreetPurplishBlue/MapServer/tile/{z}/{y}/{x}",
      Gray: "//map.geoq.cn/ArcGIS/rest/services/ChinaOnlineStreetGray/MapServer/tile/{z}/{y}/{x}",
      Warm: "//map.geoq.cn/ArcGIS/rest/services/ChinaOnlineStreetWarm/MapServer/tile/{z}/{y}/{x}",
    },
    Theme: {
      Hydro:
        "//thematic.geoq.cn/arcgis/rest/services/ThematicMaps/WorldHydroMap/MapServer/tile/{z}/{y}/{x}",
    },
    Subdomains: [],
  },

  OSM: {
    Normal: {
      Map: "//{s}.tile.osm.org/{z}/{x}/{y}.png",
    },
    Subdomains: ["a", "b", "c"],
  },

  Baidu: {
    Normal: {
      Map: "https://maponline{s}.bdimg.com/tile/?qt=vtile&x={x}&y={y}&z={z}&styles=pl&scaler=2&udt=&from=jsapi2_0",
      //   https://maponline{s}.bdimg.com/tile/?qt=vtile&x={x}&y={y}&z={z}&styles=pl&scaler=2&udt=&from=jsapi2_0
    },
    Satellite: {
      Map: "//shangetu{s}.map.bdimg.com/it/u=x={x};y={y};z={z};v=009;type=sate&fm=46",
      Annotion:
        "//online{s}.map.bdimg.com/tile/?qt=tile&x={x}&y={y}&z={z}&styles=sl&v=020",
    },
    Subdomains: "01",
    tms: true,
  },
};

L.tileLayer.chinaProvider = function (type, options) {
  return new L.TileLayer.ChinaProvider(type, options);
};
